Wireless music &amp; data transceiver system

ABSTRACT

A method and apparatus are provided for a first controlled device, such as a wireless local transmitter that accepts a plurality of digital audio signals and corresponding program information signals converted from a controlled source, such as the encoded digital data provided by a digital data signal source, typically a community antenna television (CATV) cable or direct broadcast satellite, then modulates said digital audio and corresponding program information signals on different carrier frequencies and transmits the modulated signals to a plurality of second controlled devices, such as remote digital receiver/tuners that demodulate said signals to output music in stereophonic sound and display the corresponding program information by means of an alphanumeric display. The first and second controlled devices contain microprocessor systems for communicating, controlling, storing, processing, and display of digital data within the operation of the respective system. A high speed, error free digital signal protocol is utilized for transmitting digital audio and corresponding program information signals to and from the digital receiver/tuner. The digital data transmitter and digital receiver/tuners utilize the 44.1 kilohertz (kHz) Compact Disc (CD) clock signal embedded in digital audio signals provided by an established delivery system to derive clocking signals for reception and processing of digital audio signals and for implementing the display information communications protocol.

CROSS REFERENCE TO RELATED DOCUMENTS

[0001] This application is a division of Ser. No. 08/886,951, filed Jul.2, 1997 entitled Wireless Transceiver System For Digital Music which isa continuation of provisional application Ser. No. 60/021,721, filedJul. 15, 1996 entitled Wireless Stereophonic Transmitter AndReceiver/Tuner System, said applications are incorporated herein byreference in their entirety and made a part hereof.

BACKGROUND OF THE INVENTION

[0002] This application is a continuation of provisional applicationSer. No. 60/021,721, filed Jul. 15, 1996 by Knox entitled “Wirelessstereophonic transmitter and receiver/tuner system.” The cabletelevision industry developed and refined a process of audio signalcompression in the mid-1980's. The process allows for extra space oncoaxial cable wire by electronically compressing audio signals betweenthe video bandwidths that carry the television signal. By the late1980's, audio signal compression technology spawned an industry that hascome to be known as “digital music.” Digital music is developed by cableconglomerates and is sold to subscribers along with their cabletelevision service. This audio music signal is produced at one locationby using multiple compact disc players playing continuous music in avariety of formats then sent via satellite to local cable companies. Theaudio music service is also currently available as a premium service viadirect broadcast satellite (DBS), but other methods, such as fiberoptics, telephone systems, microwaves, or Internet enabled technologiesfor example, could also deliver the signal.

[0003] The local multisystem operators (cable and DBS companies sell theservice to subscribers who pay a monthly fee for a headunit or “tuner”)compress the signal, then sell the service to subscribers. This unitdecompresses the audio signal, then converts it into an analog signalwhich can be heard through the television audio source or be used inconjunction with a home stereo component system. The user can choosefrom multiple channels using an infrared remote control or with tunercontrols located on the headunit. With the Digital Music Expressproduct, including song title, artist, album, and record label can beviewed on an LCD (liquid crystal display) window located on the infraredremote that operates the tuner as described in U.S. Pat. No. 5,445,570.This system to Cook correctly postulates the value of listener access toprogram information; specifically, that there is a strong possibilityfor loss of revenue due to subscription cancellation if a subscriber hasno method of knowing the program information that corresponds to thesong they are listening to. Furthermore, Cook explains that to the musicindustry, identification of the recording label and the musicalselection is critical to the sale of recordings.

[0004] Digital music has not developed as proponents predicted. Sinceits national introduction in the early 1990's, sales penetration hasbeen an unimpressive 1.5-2.5 percent among the multisystem operatorsoffering the service. Research has revealed that digital audio is aunique product, but with very little recognition among subscribers. And,despite a myriad of marketing schemes, neither operators nor the twomajor cable audio producers can claim to have found a definitivesolution to drive sales.

[0005] The problem with the current product is that it is not versatile.It can only interface with an existing stereo component or loudspeakersystem. Subscribers are also bound to a single choice of music locatedin the room where the converter/tuner box is located. Because the cablemusic service is not available in the convenience of technology such asa portable disc player, a portable bookshelf stereo, a portableradio/tape player, or more popular mediums for listening to electronicmusic, it will never be as attractive as it could be to the consumerswho would most appreciate its advantages.

[0006] As mentioned above, presently, the only means to access the audiosignal provided by the cable music services is through use of astationary output device, such as a rack stereo system with auxiliaryinputs for the digital music tuner. U.S. Pat. No. 5,282,028 entitled“Remote Control for Digital Music Terminal with SynchronizedCommunications” and U.S. Pat. No. 5,455,570 entitled “Methods AndApparatus For Communication Program Data Signals Via A Remote ControlUnit” incorporated herein by reference, disclose systems wherein aninfrared remote controls and communicates with a digital music tuner. Touse the tuner, changing channels or viewing program information, thelistener must be close enough in proximity to the tuner to use theinfrared remote; this can be frustrating if a variety of formats orprogram information is of interest to a listener who within sound rangebut out of the reception range of the remote control. Also, only onemusic channel can be accessed at a time, limiting all listeners to asingle music format. Additionally, if currently available tuners werecombined with multiple output devices in a single structure, competingtastes in music preference and volume would contribute to unnecessarycosts and unwanted noise pollution. Prior art has recognized the valuein wireless stereophonic signals. U.S. Pat. No. 4,829,570 to Borchardtdescribes a F.M. (frequency modulation) signal transmitter/receiversystem which is then outputted to loudspeakers. The Borchardt systemconverts an audio signal into a F.M. signal, transmits the F.M. signalover A.C. power lines, and reconverts the F.M. signal into an audiosignal which is outputted at the source. The problem with such a deviceis that it has limited function. Only one signal is sent from thetransmitter to the receiver. The receiver must be a stationary devicewith auxiliary inputs to accommodate the transmitted signal. And, thelistener must return to the signal source to change the input. RF Linkmarkets a similar product, Wavecom Jr., that transmits audio and videosignals on a gigahertz frequency, but is subject to the same limitationsof the Borchardt system. U.S. Pat. No. 5,491,839 entitled “System ForShort Range Transmission Of A Plurality Of Signals Simultaneously OverThe Air Using High Frequency Carriers” to Schotz discloses a system fortransmitting analog or digital signals. Schotz suggests that threeelectrical input signals be comprised of conventional audio sources,such as a compact disk, or tape deck, but not digital audio or programinformation to a plurality of receiver/tuners that allow a listener tointeract with the music service.

[0007] In general, such prior art systems are limited in range, signalstrength, variety of channels, program information available, andoverall accessibility and ease of use. Consequently, a requirementexists for a local transmitter and digital receiver/tuner system thatcommunicates under a control to provide reception of the digital audiomusic and display of corresponding program information which can belocated at the convenience and discretion of multiple listeners.

OBJECTS OF THE INVENTION

[0008] It is, therefore, the object of the present to provide a wirelesslocal transmitter and digital receiver/tuner system for transmitting andreceiving digital audio and corresponding program information that willovercome the limitations of conventional methods of transmitting andreceiving digital audio and corresponding program information.

[0009] It is another object of this invention to provide a transmitterthat can receive digital audio and program information input from aplurality of sources and can simultaneously broadcast a plurality ofdigital audio and program information signals over a limited range.

[0010] It is still another object of this invention to provide atransmitter that can simultaneously broadcast a plurality of digitalaudio and program information signals via a combined digital signal.

[0011] It is an additional object of this invention to provide receiversthat can simultaneously receive a plurality of combined digital audioand program information signals broadcast by the transmitter, and canselect one of the digital audio signals and display correspondingprogram information signals broadcast from the transmitter.

[0012] It is still an additional object of the present invention toutilize an existing clock oscillator having a predefined frequencywithin a first and second device to enable the transmission andreception of digital audio and program information between the twodevices using the predefined frequency to generate a wireless digitalcarrier signal.

[0013] It is a further object of the present invention to provide atwo-way communications link between a plurality of receiver/tuners andthe first controllable device which allows the listener to interact withthe service with, for example, viewing program information, participatein surveys of music preferences, or storing program information forfuture use, or purchase of music via electronic accounts.

[0014] It is yet a further object of the present invention to provide anerror detecting or an error checking process for receiving an entire,error-free message from a predetermined number of transmissions betweena controllable device and a receiver/tuner of a message defined by apredetermined number of data fields.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The following detailed description, given by way of example, andnot intended to limit the present invention solely to the embodimentsshown and described herein, will best be understood in conjunction withthe accompanying drawings in which:

[0016]FIG. 1: is a schematic representation of the overall transmitterand receiver/tuner system configured in accordance with this invention;

[0017]FIG. 2: is a block diagram of the transmitter of the system;

[0018]FIG. 2a: is a block diagram of the transmitter synchronizingcircuit.

[0019]FIG. 3: is an example of a top plan view of one variation of thereceiver/tuner units constructed in accordance with the preferredembodiments of the present invention.

[0020]FIG. 4: is a block diagram of the receiver/tuner of the system.

SUMMARY OF THE INVENTION

[0021] The problems of providing digital audio and display ofcorresponding program information associated with a digital musicservice are solved by the principles of the present invention. Thepresent invention ensures that a listener will continue to enjoy theadvantages of digital audio, while also enabling portable reception ofthe service within a localized setting. Also, the invention provides ameans for the user to participate in music surveys, store desiredprogram information, and purchase of music via electronic accounts, bycombing a wireless receiver/tuner unit that communicates with andcontrols a first controlled device, such as a digital audio and programinformation transmitter unit.

[0022] A system constructed in accordance with the present invention iscomprised of two primary components, a transmitter and at least onereceiver/tuner. The transmitter serves as an addressable controller thatincludes input means encoders/decoders associated with the system,demultiplexer, service codes, converter means, carrier signal producingmeans, combining means, and antenna means. The converter contains adigital to RF (radio frequency) converter module, demodulator,addressable control interface logic, subscriber interface logic, anddecryptor. The input means is arranged for receiving a multiplexedserial digital data audio/program information stream that includes aplurality of the digital audio, program information, and nationalsubscriber information signals from said multiplexed serial stream.

[0023] The carrier signal producing means is arranged for providing atleast a first group of carrier signals, with that group comprising a setof different carrier signals. Each of the carrier signals of the groupis preselected and is different from the others of the group, and is ata frequency of at least 900 mHz.

[0024] The modulating means is coupled to the input means for modulatingthe carrier signals of the first group with respective ones of theplurality of input signals to produce a plurality of modulated carriersignals. The serial stream is modulated using multiphase or multilevelamplitude or frequency modulation of the carrier in the F.M. broadcastband. The means for combining is coupled to the modulating means forcombing the modulated carrier signals into a combined signal and forproviding the combined signal to the antenna means. The antenna meansradiates the combined signal over the air.

[0025] The receiver/tuner is a device consisting of subcomponentsincluding a microprocessor, addressable controller interface logic, RFto digital converter, signal amplifier, tuning synthesizer, subscriberinterface logic, LCD display, demodulator, local oscillator, keypadinterface, and output amplifier. The receiver means is arranged forreceiving the combined signal and for demodulating a selected one of thecarrier signals in the group so that the input signal is extractedtherefrom for reproduction by transducer means coupled to the receivermeans.

[0026] The transmitter means provides plural groups of different carriersignals comprising plural carrier signals which are different from theother signals in that group and from the carrier signals in the othergroups and are of a frequency of at least 900 mHz. First user-selectablemeans are provided in the transmitter means and in the receiver means toselect a desired group of carrier frequencies for system operation.Second user-selectable means are provided in the receiver means toenable the user to select a desired carrier frequency of the selectedgroup to be demodulated so that they can hear the digital audio and viewthe program information signal extracted therefrom by such demodulation.The multiple groups of carrier frequencies available enables a selectionof a group of carrier frequencies which are different from those whichmay be used by another like system operation within the operating rangeof the system to ensure that there will be no interference by that othersystem.

DETAILED DESCRIPTION OF THE INVENTION

[0027] With reference first to FIG. 1, a system is illustrated thereinfor local wireless transmission and reception of digital audio andprogram information. A delivery system 10, such as coaxial cable,satellite, the Internet, microwave, and etc., outputs a serial digitalaudio/program information stream 22 that contains digital audio, programinformation, and national subscriber information. The transmitter 100,more fully described with respect of FIGS. 2-2 a, receives the saidserial digital data stream 22 and demultiplexes, decrypts, and decodesthe digital audio and program information signal. The digital audiosignal and program information are converted to a digital RF carrierfrequencies and broadcasted to a plurality of second devices, preferablyat least one receiver/tuner unit 200, more fully described with respectof FIGS. 3-4, that outputs the selected audio electronically anddisplays the corresponding program information of the audio trackcurrently listened to by the subscriber.

Digital Music Transmitter

[0028]FIG. 2 is a block diagram of the preferred digital musictransmitter (DMT) 100. Referring to FIGS. 1-2, the serial digital datastream 22 is passed via an established system of digital datadistribution 10, for example, multisystem operator's coaxial cable ordirect broadcast satellite, and is received by the transmitter inputterminal 105. The transmitter input terminal 105 preferably includesphase-lock loop (PLL) circuitry. The signal is amplified by an amplifier110 and filtered by a SAW filter 115 before being demodulated by ademodulator 120. The demodulator 120 converts the selected digitalfrequency to demodulation intermediate frequency (IF). The output of thedemodulator 120 is quadrature partial response (QpR) demodulated toproduce a 5.6 Mbps data stream containing 150 stereo pair of digitalaudio data to an applications specific integrated circuit (ASIC) 130.The demodulator 120 provides data to a data clock recovery PLL 125. Thedata clock recovery PLL 125 contains a 33.8688 mHz crystal 122 (about33.9 mHz) for timing purposes.

[0029] The ASIC 130 provides demultiplexing, decrypting, and decodingoperations upon the 5.6 Mbps data stream input by the demodulator 120 tothe microprocessor 140. The ASIC 130 separates the 5.6 Mbps data streamto a select one of 150 stereo pairs of digital audio signals. Theselected stereo pair is decrypted and separated to provide digital audiosignal and a program information signal. The digital audio signal isthen decoded according to a variety of known techniques. The ASIC 130inputs the digital audio signals, provided at a sampling rate of 44.1kilohertz (KHz), to a digital RF converter 150. The audio signals areprovided to a F.M. stereo encoder and loudness processor 152, and thento F.M. band exciter 154. The output of the exciter 154 is amplified bya high power amplifier 156 and broadcast over the airwaves by an antenna160 as digital F.M. in the F.M. broadcast for reception by a digitalF.M. receiver 201, such as disclosed in FIG. 3.

[0030] A receiver 170 for a second controllable device, such as adigital receiver/tuner (DRT) 200, coupled to the microprocessor 140receives instruction or control signals transmitted by the DRT 200 toinitiate the remote control of selected functions of the transmitter100. A clock signal generated internal to the ASIC 130 is utilized as acarrier signal to switch the output of the DRT 200 ON or OFF at afrequency of 44.1 KHz. The 44.1 KHz clock from an ASIC Clock generator130 a may be utilized to generate a carrier signal for RF signals sentby the DRT transmitter 160. The ASIC Clock signal provided by the ASICclock 130 a is derived from the about 33.9 mHz signal provided to theASIC 130 by the data clock PLL 125. The DRT 200 operates to controlselected function of the transmitter as well as the program informationtransmitted by the DRT transmitter 160 associated with the DMT 100.

[0031] The ASIC Clock signal provided by the ASIC clock 130 is derivedfrom the about 33.9 mHz signal provided to the ASIC 150 by the dataclock PLL 125. Specifically, the ASIC Clock signal is derived bydividing the 33.9 mHz signal by three (3) to provide a second clocksignal having a frequency of 11.3 mHz, and by then dividing the 11.3 mHzsignal to the preferred fixed first frequency for the 44.1 kHz ASICClock signal. The 11.3 mHz clock signal is utilized as a clock signalselected operations conducted by the ASIC 130. The ASIC 130 contains asynchronizing circuit 132 which is utilized to provide clocksynchronized program information signals to the DRT 200. Thesynchronizing circuit 132 operated to provide two separate timingalignment functions. First, the synchronizing circuit 132 aligns theprogram information signal provided by the microprocessor to the 11.3mHz clock signal. Second, the synchronizing circuit 132 aligns the 44.1KHz ASIC Clock signal to the 11.3 mHz clock signal.

[0032] Referring to FIGS. 2-2 a, the synchronizing circuit 132 includesa first synchronizing element 133, an edge detector 134, and secondsynchronized element 135, and gate 136. The microprocessor 140 providesprogram information signals in the form of a serial data signalformatted in the appropriate display information protocol to the firstsynchronizing element 133. The microprocessor 140 outputs the programinformation signals to the first sychronizing element 133 at apredefined data rate, preferably 4900 baud. In addition, the 11.3 mHzclock signal is provided as another input to the first synchronizedelement 133. The first synchronizing element 133 aligns the rising edgeof the program information signals to the 11.3 mHz clock signal toprovide an output signal synchronized with the 11.3 mHz clock. Thesecond synchronizing element 135 accepts the synchronized output signalof the first synchronizing element 133 and produces a gate signal whenthe output signal of the edge detector 134 enables the secondsynchronizing element 135. The gate signal produced by the secondsynchronizing element 135 and the ASIC clock signal of 44.1 kHz areprovided as inputs to an AND gate 136. Accordingly, the integral numberof cycles of the ASIC clock signal output by the AND gate 136 iseffectively determined by the pulse width or pulse duration of the gatesignal output by the second synchronizing element 135.

[0033] The output of the ASIC 130 is a carrier-modulated programinformation signal, produced by an on/off keying technique, and isprovided from the synchronizing circuit 130 on line 137 to the DRTtransmitter 160. The carrier-modulated program information signal, whenformatted with appropriate start bits, stop bits, and other formattinginformation described below, comprises a display information signal thatis ultimately display as alphanumeric characters on the display of theDRT 200. The DRT transmitter 160 is responsive to the carrier-modulatedprogram information signal provided on line 137. The microprocessor 140initiates a transmission of a program information signal by the DMT 100.In response to the initiation of a transmission, the ASIC 130 outputsthe synchronized program information signal at the rate defined by thefirst frequency (44.1 KHz) to the DRT transmitter 160.

[0034] The DRT receiver 170 includes a demodulator 172 and RF diode 174.The RF diode 174 is located between an input of the demodulator 172 andthe ground. When the RF diode 174 detects a command signal from the DRT200. The RF diode 174 outputs a detected signal to the demodulator 172.The demodulator 172 demodulates and filters the detected RF signal andprovides an output voltage signal to the receiver input terminal of themicroprocessor 140 on line 173. The demodulator 172 provided thespecific functions preamplification, bandpass filtering, and detectionof the detected RF signal provided by the RF diode 174.

Digital Receiver/Tuner

[0035]FIG. 4 is a block diagram of the preferred digital receiver/tuner(DRT) unit 200. The preferred DRT units, not limited to the embodimentsin FIG. 3, include a display for the control of the digital musictransmitter (DMT) 100. The top surface of the DRT 200 includes analphanumeric character display and a matrix of contact switches forminga keypad. Each contact switch of the keypad is covered by a push buttonor key that includes a label which defines the function or instructioninitiated when the user presses the push button. In addition, selectedareas of the tip surface of the DRT unit include labels or other indiciathat further designate the function or instruction associated with thekey or push button. The user can control the functions of the DMT 100 ina manner similar to the use of currently popular wirelesstransmitter/receiver units that control the functions of consumerproducts, such as cordless telephones or local audio signal transmitter.

[0036] Specifically, the DMT 100 remains in a dormant mode with atransmitted passive signal that responds to a selected command functionfrom the DRT unit 200. The user can initiate or terminate transmissionof the digital audio and program information from the DMT 100 bypressing a selected key. Each of the buttons or key of the keypad islabeled to indicate the function associated with the key.

[0037] For example, by pressing any key or a set of keys labeled withArabic numerals 0-9, a user can select one of the available digitalaudio and program information channels transmitted by the DMT 100 forthe listening pleasure of the subscriber. The keys labeled TUNE (uparrow) and TUNE (down arrow) may be used by the listener to increment ordecrement the digital audio and program information channels transmittedby the DMT 100. In a similar fashion, a volume up (VOL up arrow) and avolume down (VOL down arrow) keys can be utilized to control the volumelevel provided by the DMT 100. An ON/OFF key with a power indicatorlight may be utilized by the listener to either power on or off the DRT200 and DMT 100 signal transmission. Also, a MUTE key is useful foreliminating the audible portion of the program provided by the DMT 100.Those persons skilled in the art will appreciate that such controlfunctions are similar to the control function provided by other wirelessremote controls for consumer products.

[0038] Other control function related to the control of the DMT 100 bythe DRT unit 200 include control functions associated with the keysENTER/NEXT, PRESET and MODE. By pressing the ENTER/NEXT key, the userinitiates a command function that may be associated with the variousfunctions of the DRT unit 200. The PRESET key permits the user to storea favorite digital audio channel for future operations by the DRT unit200. The MODE function changes the message field on the LCD viewscreenaccording to selected function by the user, for example viewing orstoring program information for a current music selection, participatingin music surveys, or purchase of music via electronic account.

[0039] The listener can also review the program information associatedwith a current program by inputting an information request fortransmission to the DMT 100. By pressing the VIEW key, the userinitiates the transmission of an information request by the DRT unit 200to the DMT 100. The DMT processes the information request and initiatesa search for program information associated with the current program. Ifthe program information is not found by the DMT within a predeterminedtimer period, typically about five seconds, the DMT 100 will respond tothe transmitted information request by transmitting an error message tothe DRT unit 200. If the search by the DMT 100 is successful, the DMT100 will respond to the transmitted information request by transmittingthe program information to the DRT unit 200. With respect to digitalaudio signals, a typical program message includes information concerningthe composer, the track title, the artist, the album associated with thetrack title, and custom information concerning the current performance.

[0040] Referring to FIG. 4, the preferred DRT unit 200 includes aprocessor 240, preferably a microcomputer or microcontroller, havingon-board mask programmed memory, such as a read only memory (ROM) 240 a.The memory 205 a comprises plurality of memory locations for storingparameters associated with different control signal protocols (inparticular, for storing a plurality of parameters associated withdifferent control protocols for different controllable devices). Thepreferred DRT unit 200 further includes a RF receiver 201, demodulator218, an applications specific integrated circuit ASIC 230, digital/audioconverter 270, transmitter 260, a data clock recovery PLL 225, frontpanel interface 250, stereo output amplifier 280.

[0041] The output of the demodulator 218 is quadrature partial response(QpR) demodulated to produce a 5.6 Mbps data stream containing 150stereo pair of digital audio data to the ASIC 230. The demodulatorprovides data to a data clock recovery PLL 225. The data clock recoveryPLL 225 contains a 33.8688 mHz crystal 122 (about 33.9 mHz) for timingpurposes. In the preferred embodiment, the DMT 100 control signalprotocols are stored in the ROM 240 a. The control protocol includes theproperly formatted codes associated with control functions for the DMT100.

[0042] The ASIC 230 provides demultiplexing, decrypting, and decodingoperations upon the 5.6 Mbps data stream input by the demodulator 218 tothe microprocessor 170. The ASIC 230 separates the 5.6 Mbps data streamto a select one of 150 stereo pairs of digital audio signals. Theselected stereo pair is decrypted and separated to provide a programinformation signal and a digital audio signal. The digital audio signalis then decoded according to a variety of known techniques. The ASIC 230inputs the digital audio and program information signals, provided at asampling rate of 44.1 kHz, to a digital/audio converter 270, transmittercontrol 260, and microprocessor memory 240 a. The demultiplexed controland channel data separated out from the data steam by the ASIC 230 areprovided to a microprocessor 240 which controls the overall operation ofthe DRT unit 200.

[0043] A clock signal generated internal to the ASIC 230 is utilized asa carrier signal to switch the output of the DRT 200 ON or OFF at afrequency of 44.1 KHz. The 44.1 KHz clock from an ASIC Clock generator230 a may be utilized to generate a carrier signal for RF signals sentby the DRT transmitter 160. The ASIC Clock signal provided by the ASICclock 230 a is derived from the about 33.9 mHz signal provided to theASIC 230 by the data clock PLL 225. The DRT 200 operates to controlselected functions of the DMT 100 as well as the program informationtransmitted by the DRT transmitter 260 associated with the DMT 100.Referring to FIG. 2a, the ASIC Clock signal provided by the ASIC clock230 a is similar in function and purpose to that of the aforementionedASIC clock 130 a. As result, the 11.3 mHz clock signal is utilized as aclock signal selected operations conducted by the ASIC 230.

[0044] Referring again to FIG. 4., for a first operation mode, digitalaudio and program information carrier signals are received by thereceiver antenna 201 from the DMT transmitter 160. The received signalis provided to a double tuned tracking filter (DTTF) with PLL circuitry,from there to an amplifier 203, on to a single tuned tracking filter(STTF) 205, a mixer 207, and SAW filter 209, and into a demodulator 218,according to known techniques. The channel selection process is undercontrol of a tuning synthesizer 220, integrating amplifier 217, STTF215, and amplifier 212, interconnected as shown and impressing anappropriate signal on a line 211 to the DTTF 201, STTF 205, andoscillator 210 to effect channel selection, according to knowntechniques. The program information signal from the ASIC 230 is sent tothe microprocessor 240 where it may be displayed on the front panelinterface 250. The ASIC 230 also sends the program information signal tothe transmitter interface 255 and transmitter control 260 fortransmission to the DMT 100. Channel selection is provided by theinfrared receiver and/or front panel interface 250, which information ispassed on by the microprocessor 240 to the tuning synthesizer 220.

[0045] The ASIC 230 inputs the digital audio and program informationsignals, provided at a sampling rate of 44.1 kHz to a digital/audioconverter 270. The output of the D/A 270 device is provided as a datastream over a bus to a logic circuit 274 with separates the dates streaminto control bits and channel indication (tag bits) and encrypteddigital audio bits (demultiplexing functions) and decrypts the digitizedaudio data into a suitable form for a Dolby decoder 278. The audio datais decrypted into three serial streams per audio channel consisting ofbasic delta modulation parameters for “left” and “right” channels. Theoutput of the Dolby decoder 278 is provided as “left and “right” audiochannels to a stereo amplifier 280, and to stereo outputs for use withstandard audio components.

[0046] From the foregoing description of the preferred embodiment, itwill be appreciated that the present invention overcomes thedisadvantages of the prior art and achieves the objects and advantagesof the invention recited above. Accordingly, the invention improvesexisting methods of providing digital music by making the service moreconvenient and accessible to subscribers through wireless transmissionof music to remotely located devices. Greater recognition amongsubscribers is gained by similarities of the preferred embodiments tomore popular consumer electronic music devices. And, digital music ismade more versatile with improved methods of subscriber interaction withthe service. The above description of the invention is intended to beillustrative and not limiting. Various changes or modifications in theembodiments described may occur to those skilled in the art and thesecan be made without departing from the spirit or the scope of theinvention.

What is claimed is:
 1. A method of locally broadcasting and controllinga plurality of digital data signals, said at least to one remotelylocated second device being operative to carry out controllable functionupon receipt of a command delivered by a control signal from the firstdevice, comprising; A transmitter device transmitting digital audio andcorresponding program information with control signals corresponding tosaid selected commands to at least one remotely located second device inresponse to said digital audio, program information, and commandsignals; and At least one receiver/tuner device responsive to thedigital audio and program information signals and corresponding controlsignals by said controlled device, said program information comprisingalphanumeric information; and A microprocessor circuit receiving andcontrolling an operator input corresponding to a selected command fordelivery to said at least one remotely located second device andproviding a command signal; and A display displaying alphanumericcharacters associated with said program information and selectedcommands corresponding to said signals.
 2. The system of claim 1 ,further comprising second transmitting means associated with said seconddevice, said transmitting means being simultaneously operative fortransmitting a digital audio request signal and for transmitting aninformation request signal from said second device to said first device,and wherein said first device is responsive to said digital audiorequest signal for transmitting said digital audio and said first deviceis responsive to said information request signal for transmitting saidseparated information signal.
 3. The system of claim 1 , wherein saiddigital data signal source is a multiplexed serial digital data stream.4. The system of claim 1 , wherein said digital data signal comprisesdigital audio, corresponding program and system information, nationalsubscriber information, and control signals corresponding to saidselected commands from first and second controlled devices.
 5. Thesystem wherein a first controlled device transmits a plurality ofdigital audio signals of audio source material corresponding to aselected set of digital data to at least one second controlled device,comprising: (a) a first controlled device including: first receivermeans for receiving a plurality of said digital audio signals to providea received plurality of said digital audio signals; first processormeans, coupled to said first receiving means, for processing saidreceived digital signal to provide a selected one of said digital datasignals and a selected one of said information signals that is separatedfrom said corresponding one of said digital data signals; and clocksignal generator means, coupled to said first processor means, forproviding a clock signal having a first frequency; and means, coupled tosaid receiver means, for modulating a plurality of RF carriers with saiddigital audio using multilevel modulation to produce a plurality of RFchannel signals; means, coupled to said modulating means, fortransmitting the RF channel signals; (b) a second controlled deviceincluding; second receiving means for receiving a plurality of said RFsignals to provide a received plurality of said digital audio signals;tuner means associated with said second receiving means for tuning aselected one of a plurality said digital audio signals; digitaldemodulator means, coupled to an output of said tuner, for demodulatinga multilevel modulated plurality of said digital audio signals; anddecoder means, coupled to said digital demodulator means, for processingthe demodulated plurality of said digital audio signals into left andright stereo channels for audible reception.
 6. The system of claim 5 ,wherein said transmission protocol includes a starts text field, amessage sequence field, a plurality of data definition fields, aplurality of data fields, a plurality of error detection fields, amessage error detection field, and an end of text field.
 7. The systemof claim 5 , wherein at least one of said channels of audio sourcematerial comprises left and right stereo channels signals for digitaltransmission together in a channel allocation corresponding to saiddecoder means.
 8. The system of claim 5 , wherein said RF signal is adigital data signal comprising digital audio, program information, andnational subscriber information.
 9. The system wherein a firstcontrolled device transmits information corresponding to a selected setof digital data to at least one second controlled device, comprising:(a) a first device, comprising first receiving means of receiving adigital data signal, said digital data signal provided by a remotesignal source and containing a plurality of information signals and aplurality of digital audio signals, each of said information signalshaving a corresponding one of said digital audio signals, to provide areceived digital data signal; and first processor means, coupled to saidfirst receiving means, for processing said received digital signal toprovide a selected one of said digital data signals and a selected oneof said information signals that is separated from said correspondingone of said digital data signals; and clock signal generator means,coupled to said first processor means, for providing a clock signalhaving a first frequency; and first transmitting means, coupled to saidfirst processor means, for transmitting said selected one of saiddigital data signals and said selected one of said information signalsat a rate defined by said first frequency to produce a transmittedinformation signal; and (b) a second device, remotely located from saidfirst device, comprising: second receiving means for receiving saiddigital data signal and said transmitted information signal to provide areceived information signal; and second processor means, coupled to saidsecond receiving means, for processing said received digital data signaland said received information signal; and communicating means, coupledto said second processor means, for communicating said received digitaldata signal and said received information signal; and receiving means,coupled to said second processor means, for audible output of saidreceived digital data signal; and processing means, coupled to saidsecond processor means, for storing and processing of said receivingdigital data signals and said received information signals; and secondtransmitting means, coupled to said first processor means, fortransmitting said selected one of said digital data signals and saidselected one of said information signals at a rate defined by said firstfrequency to produce a transmitted information signal.
 10. The system ofclaim 9 , wherein said transmitted information signal comprises amessage containing said information, said message having a transmissionprotocol defined by a plurality of fields.
 11. The system of claim 5 ,wherein said clock frequency is 44.1 kHz.
 12. The system of claim 5 ,wherein said clock generator signal is simultaneously operative forproviding said a clock signal and at said clock frequency forutilization of said digital audio signal and for utilization by saidfirst transmitting means for transmitting said separated informationsignal.